Bilateral Medial Patellar Luxation Research Articles

Luxação patelar medial bilateral em cão, grau III: Relato de caso

Medial patellar luxation is an orthopedic problem commonly found in small breed dogs, whose treatment is surgical. This paper aims to report a case of grade 3 bilateral medial patellar luxation. A 5-year-old, uncastrated Maltese female dog was admitted to the Veterinary Hospital of the University of Sorocaba, diagnosed with a bilateral medial patellar luxation grade 3. The surgical procedure performed for patellar arthroplasty of the left pelvic limb, in this type of degree, has a favourable prognosis.

Bilateral Patellar Groove Replacement in a Dog with Iatrogenic Trochlear Groove Damage

A 2-year-old, 1.94 kg spayed female Toy Poodle was referred for revision surgery for patellar reluxation following surgery for bilateral medial patellar luxation (MPL). Intermittent non-weight-bearing lameness of the right hindlimb and weight-bearing lameness of the left hindlimb were evident on general inspection. A physical examination revealed that there was a bilateral grade 4 MPL. On radiographs, the medial and lateral trochlear ridge was bilaterally worn out. Patellar groove replacement (PGR) was performed in two stages to replace the bilateral femoral trochlea that had a severely worn out groove. Corrective femoral osteotomy with increasing anteversion angle, tibial tuberosity transposition, medial releasing, lateral imbrications and PGR were performed on the right hindlimb. Six months after surgery on the right hindlimb, a PGR prosthesis was positioned medially on the frontal plane and tibial tuberosity transposition and lateral imbrications were performed on the left hindlimb. Two weeks after surgery, reluxation of the patella occurred on the left hindlimb. The tibial tuberosity transposition was performed to realign the patella more laterally than the previous surgery, and a patellar sling was applied. Two years after the last surgery, the patient showed no pain on the stifle joint and satisfactory weight-bearing ambulation. Reluxation did not recur. PGR maybe a successful treatment for dogs with iatrogenically damaged and/or worn out patellar grooves.

Postoperative Complications and Short-Term Outcome Following Single-Session Bilateral Corrective Surgery for Medial Patellar Luxation in Dogs Weighing

To assess complication rates and short-term outcome in small dogs with bilateral medial patellar luxation (MPL) undergoing single-session bilateral corrective surgery. Retrospective case series. Dogs weighing <15 kg with congenital bilateral MPL that underwent single-session bilateral corrective surgery (n = 50). Surgical procedures for MPL correction included trochlear wedge recession (TWR), crest transposition, lateral imbrication, and medial fascial release. Complication rates were correlated with number of surgical procedures, weight, whether or not a bandage was applied postoperatively, and surgeon experience (ACVS Diplomate vs resident). Results were compared with the most recent study evaluating single-session bilateral corrective surgery for MPL. Overall complication rate was 22% (11 of 50 dogs). Implant failure occurred in 2 dogs (3 stifles) requiring revision. Grade 1 patella reluxation was the most common minor complication at 10% (5/50). Overall complication and reluxation rates were similar to previous studies. There were no intraoperative complications after performing TWR in small dogs. Single-session bilateral corrective surgery for MPL is well tolerated in small dogs with complication rates historically similar to dogs undergoing unilateral or staged bilateral surgery. With individual case assessment, single-session surgery could be offered to owners, allowing one anesthetic episode and potentially lowering the chance for morbidity. Further studies, ideally prospective studies, are needed toassess long-term outcome following single-session bilateral corrective surgery forMPL.

Arthroscopy for the Diagnosis and Treatment of Failed Trochleoplasty in a Dog

A 3-year-old castrated male Spitz dog (8.4 kg) was referred for hindlimb lameness. The dog had undergone corrective surgery for bilateral medial patellar luxation 6 weeks prior to presentation. Intermittent lameness of both hind limbs was evident on general inspection. Physical examination revealed moderate pain and crepitus upon flexion and extension of the stifle joints. Radiography revealed features consistent with distal deviation of the cartilage flaps and effusion in both stifle joints. Detachment and deviation of both osteochondral blocks were suspected based on the physical and radiographic findings. Arthroscopy confirmed failed osteochondral blocks (right 1.5 cm × 0.9 cm × 0.2 cm, left 1.3 cm × 0.9 cm × 0.1 cm), which were removed. After removal of the osteochondral blocks, the stepped trochlear grooves were located and debrided using an arthroscopic burr, to prevent patellar tracking disorder. The dog resumed normal ambulation without medial patellar luxation 2 weeks postoperatively, and there were no complications. Arthroscopy is an effective surgical modality for the diagnosis and treatment of canine joint disorders. It offers a magnified view of the joint, which allows accurate evaluation of intra-articular structures. In addition, arthroscopic surgery can reduce the postoperative complications associated with surgical wound.

Spinal Syringomyelia Secondary to an Intracranial Microcystic Meningioma in a Dog

A 5-year-old, 2.7 kg female maltese dog was presented a local veterinary clinic with one week history of hindlimb lameness associated with patellar luxation. Reduction of bilateral medial patellar luxation was operated using trochlear resection and lateral reinforcement technique. Three weeks after the surgery, the dog showed bending spine with pain in thoracic and lumbar region, continuous ataxia and intermittent convulsion. Magnetic resonance imaging scanning revealed a hyperintense mass in right frontal lobe of brain and abnormal cavitation from cervical cord to third lumbar cord. Histopathologically, neoplasm in brain composed of meningothelial cells showed loosely reticular or lace-like morphology with numerous extracellular cystic spaces of variable size and shape. Neoplastic cells were positive for vimentin and negative for neuron specific enolase and glial fibrillary acidic protein. Irregular shaped enlarge central canal-like cavity was existed in cervical and lumbar cords. In our best knowledge, this report described the clinical findings, imaging and histopathologic characteristics of unusual intracranial microcystic meningioma with secondary syringomyelia in a dog.

Severity of patellar luxation and frequency of concomitant cranial cruciate ligament rupture in dogs: 162 cases (2004–2007)

To evaluate severity of medial patellar luxation (MPL) and frequency of concomitant cranial cruciate ligament rupture (CCLR) in dogs. Retrospective case series. 162 dogs (266 stifle joints). Medical records of 162 small-breed dogs with MPL were reviewed. Signalment, body weight, luxation grade, bilateral or unilateral MPL, CCLR, and difference in luxation grades between stifle joints were evaluated. Association between severity of MPL and CCLR was investigated. 58 dogs had unilateral MPL, and 104 dogs had bilateral MPL. Dogs ranged from 8.4 months to 16.7 years of age (mean, 5.7 years), and mean body weight was 5.45 kg (12 lb). Forty-one percent of all dogs had concomitant CCLR. Mean age for dogs with MPL alone was 3.0 years, which differed significantly from mean age of dogs with MPL and concomitant CCLR (7.8 years). Dogs with grade IV MPL were significantly more likely to have concomitant CCLR than were dogs with any other grade of MPL. In dogs with bilateral MPL and unilateral CCLR, there was a significantly higher grade of luxation in the stifle joint with CCLR. Small-breed dogs with MPL and concomitant CCLR were older than were dogs with only MPL. Dogs with grade IV MPL were more likely to have CCLR than were dogs with other grades of MPL. Most dogs with concomitant CCLR had a higher MPL grade in the affected stifle joint than in the intact joint. These findings should be beneficial in client education and clinical diagnosis.

Evaluation of the association between medial patellar luxation and hip dysplasia in cats

Objective To investigate the association between hip dysplasia (HD) and medial patellar luxation (MPL) in cats. Design Cross-sectional prevalence study. Animals 78 cats. Procedure A complete history was obtained. Cats were examined to detect MPL and HD. Radiographs of the stifle and hip joints were obtained. Hip joints were evaluated by use of Norberg angle, distraction index, and scoring consistent with that established by the Orthopedic Foundation for Animals. Results There were 43 male and 35 female cats (mean age, 2.5 years). Eleven cats had clinical signs of disease in the pelvic limbs. Medial subluxation of the patella (subgrade 1) was seen in 31 of 33 cats with otherwise normal stifle joints. Medial patellar luxation was found in 45 of 78 (58%) cats, and 35 of 45 (78%) had grade-1 MPL. Bilateral MPL was seen in 32 of 45 (71%) cats. A weak association existed between MPL and HD, because cats were 3 times more likely to have HD and patellar luxation than to have either condition alone. Concurrent MPL and HD were detected in 19 of 78 (24%) cats, and HD was diagnosed radiographically in 25 of 78 (32%) cats (19 mild, 4 moderate, 2 severe). Eighteen of the 25 cats with HD had bilateral HD. Conclusions and Clinical Relevance Clinically normal cats may have a certain degree of laxity in the stifle joint, evident as medial patellar subluxation (&lt; grade 1). There is a weak association between MPL and HD, and both conditions may develop, alone or in combination, more frequently than has been reported. (J Am Vet Med Assoc 1999;215:40-45)

Medial patellar luxation in 16 large dogs. A retrospective study.

Unilateral medial patellar luxation was diagnosed in 10, and bilateral medial patellar luxation in six, large and giant-breed dogs (22 stifles). Lameness occurred in five dogs after trauma or surgery, and 11 dogs had no known predisposing history. The mean age at presentation was 25 months, and the mean time from initial onset of clinical signs to diagnosis was 13 weeks. All traumatic or iatrogenic luxations (five dogs) were unilateral. Luxations presumed to be congenital were unilateral in five dogs and bilateral in six. The grades of medial patellar luxation were I (1 stifle), II (11 stifles), III (9 stifles), and IV (1 stifle). Preoperative function was good (1 dog), fair (9 dogs), and poor (6 dogs). Surgical correction was performed in dogs with grades II, III, and IV luxations (21 stifles). Complications included one wound dehiscence and trochlear wedge migration, one pin loosening, and one persistent lameness caused by lymphoplasmacytic synovitis. Long-term follow-up was available in 13 dogs (18 stifles). Function was judged by owners to be excellent in seven dogs, good in five dogs, and poor in one dog. Surgical treatment of grades II and III luxations yielded good (8 stifles) and excellent (9 stifles) results, while one grade IV luxation had a poor long-term outcome.